Colour
Colour laser printers are a relatively new development, until recently it had proved difficult to handle the paper accurately enough to position the four images required (cyan, magenta, yellow and black) exactly on top of each other. The colour printer works in the same way as a monochrome printer, except that it prints on the paper four times. Colour printers still use one photoreceptor, but successively transfer the colours to the paper, one at a time, to build up the image.
Most colour printers are designed as specialist workgroup products, so that they can be shared between several users who need colour. The speed of colour printers is low, typically 2 - 8 p.p.m. in colour mode, so they are normally only used for colour printing, and a separate conventional monochrome printer is used for normal printing.
There are a few colour printers which can operate in both colour and monochrome modes. These printers normally print monochrome as efficiently as a dedicated monochrome printer, slowing down to print the colour pages in a print job, and so can be used as a normal workgroup printer with the facility to produce occasional colour prints.
The majority of colour laser printers provide a Centronics parallel port and a serial port, and a range of network connectivity options befitting their status as shared devices.
The complex mechanisms of colour laser printers means that they are normally rather larger than the equivalent monochrome printer, which in turn provides space for several paper trays, but in general the slow speed of colour printers confines them to a specialist role, and the range of input and output options for them is limited.